Adding to what LiberalLucario started hinting at,
What I find to be more curious about the Victini ban which in my opinion was overdue come BW2 than the hole Darmanitan, Arcanine, and Entei are left to fill, is the effect that its removal will have on more passive playstyles. Having already lost Heracross adds to this even further.
Passive and defensive playstyles were never not-viable when Victini and Heracross were around, even before I left. Victini's mild unpredictability and sheer power regardless of set usually meant a lot of guesswork for defensive teams, potentially leading to something dying if you didn't have a dedicated Victini check (which was usually a sure sign of a bad team). Heracross became an even bigger burden on former checks (read Cofagrigus) when Knock Off got its obscene buff too. Defensive teams had lost a lot of ground since XY started, as each generation brings a power creep, but it looks like some of that momentum is coming back. Now, just taking a quick glance at the Viability Ranking Thread, I can really see bulky offense take off even further, as there isn't as big of a burden to have such fat Pokemon on it now.
I'm not going to comment on Togekiss really. It was nearly unbearable last generation, and it sounds like it was as bad, if not worse this generation. Not really surprised there.